The overall objectives of the project are to develop new experimental techniques that are needed and carry out appropriate research to further the extension and testing of theories concerning the way in which the adjustment of organisms to their environment is modified by rewarding and punishing consequences of actions. Special attention is given to the specific application of these theories to human behavior and the development of significant relationships between general learning theory and information processing approaches. A substantial array of previous results concerning transfer behavior following training on differential reward magnitudes has been well accounted for by a model based on a conception of memory for categorical frequency information. A major extension of this work during the current year has provided a picture of memory for frequency of events over much longer time intervals and for much larger frequencies than previously studied. In the continuation we hope to develop a model integrating these new results with existing theory. The second main activity for this year is further development of an experimental paradigm and pilot work on human choice behavior in relation to analog regards. A principal limitation of previous work has been the use of discrete, readily verbalizable reward values such as amounts of money, "points", or tokens. The work will involve two stages, first determining how an individual encodes and remembers differential reward values on a continuous scale and then relating these to choices in a number of situations paralleling those that have been studied in the past only with discrete rewards.